Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description adds substantial behavioral detail beyond the annotations: it clicks the candidate or its single inner button/link, blocks write requests, navigation, and new windows, verifies that new content appeared, preserves existing ids while assigning new ones, and explains the Panel reload behavior. It also documents refusal reasons, private-site restrictions, parallel execution, and the approximate 45-second timeout responses.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is front-loaded with the core purpose and all sentences carry operational information, including return shape, id stability, refusals, private-site restrictions, and timeout behavior. It is somewhat long and monolithic, but the density is justified by the complexity of the tool.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the absence of an output schema, the description explains the return format in useful detail: updated tree lines like `open_page`, new candidates, outline, and id behavior. It also covers safety constraints, refusal conditions, private sites, parallelism, and timeout handling, so an agent has enough context to invoke it correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 0% schema description coverage for two required parameters, the description partially compensates by framing `page` as an open page and `candidate` as the control to click, including the case where it contains exactly one button or link. However, it does not explicitly define the expected id formats, where `page` comes from, or how `candidate` relates to ids returned by `open_page`.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb and resource: revealing content hidden behind a control on an open page, with examples such as tabs, expand toggles, disclosures, and 'more' buttons. It is clear what the tool does, but it does not explicitly differentiate itself from the sibling `expand` tool, leaving the agent to infer when one is preferable.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives explicit usage conditions (hidden content behind a control on an open page), exclusions (never on the user's Private sites; refuse when navigation, new window, path change, or no new content occurs), and an alternative approach for refused cases (use content reachable by URL instead). It also notes that reveals on different pages may run in parallel.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.